1. Field of the Invention
The present invention relates to printers of the ink jet variety and more particularly to a system for concentrating and containing waste ink in such printers.
2. Description of the Related Art
Conventional ink jet printers require a storage device for accumulating waste ink due to printhead maintenance, which requires jetting of ink droplets periodically to clear contamination from nozzles or to ensure proper ink chemistry at the nozzle openings. More recent inks have become more difficult to maintain, due to customer expectations of faster throughput, greater optical density, and less bleeding into the print media. Each of these results in inks which require more jetting to properly maintain the printheads and an associated increase in the quantity of waste ink to be controlled.
A common method of accumulating waste ink is to capture it in an absorbent material (referred hereafter as a diaper) to prevent contamination due to printer orientation. A diaper would normally be placed in an open tray, or some other type of open container. A complete saturation of the diaper causes flooding, or spilling, in a printer that uses diapers in the traditional manner. With the increased waste requirements due to increased throughput and printer life, the volume of felt material can become substantial. As an example, certain commercially available printers have diapers that line nearly the entire bottom surface of the printer. Even so, under certain conditions such as high duty cycle, or duty cycle bursts late in printer life, the probability of waste overflow becomes increasingly high. Further, pigment based inks tend to render absorbent material ineffective due to pigment bridging of the capillary paths. As a result, an alternate technique of managing pigment ink waste is sometimes required.
In many cases, space constraints do not allow for adequate diaper size. For these applications, a diaper is used to perhaps cover an open container to minimize splashing of waste ink in the event the printer is transported. This method can only be used for printers with a relatively short recommended life, thus less waste ink. The uncertainty of actual life, however, in addition to duty cycle uncertainties, renders this method inferior.
Critical to managing ink waste is evaporating the xe2x80x9cfast volatilesxe2x80x9d, such as water, from the ink as efficiently as possible. This reduces the risk of spillage, or overflow, and reduces the volumetric requirements for waste containment. Another critical design element is to provide adequate, but not excessive, volumetric requirements for ink waste.
The present invention optimizes available and cost effective components that, as a system, maximize evaporation and minimize volumetric waste requirements. Further, the present invention provides a robust method of spillage or overflow containment.
The invention comprises, in one form thereof, a process in which ink jet printer waste ink from a printhead is transferred to a surface across which air is forced to promote evaporation of certain volatile ink components from the ink. The surface may comprise an absorptive diaper.
Also in general, and in one form of the invention, waste ink from an ink jet printer printhead is controlled by depositing the waste ink on a region, exposing the deposited ink to an air flow to promote evaporation of certain volatile ink components, and transferring at least some unevaporated ink from the region to a spill-resistant container.
An advantage of the present invention is an increased waste ink disposal capability with minimum retention capacity requirements.
Another advantage is waste ink confinement with reduced spillage potential.
Yet another advantage is effective waste ink containment by quickly evaporating certain volatile ink components prior to containment, securely retaining the unevaporated components, and allowing for additional evaporation subsequent to containment.